[turbofan] Optimize typeof in abstract/strict equality comparison.

src/compiler/typer.cc

Index: src/compiler/typer.cc
diff --git a/src/compiler/typer.cc b/src/compiler/typer.cc
index 2ac137641d54cab8605cb1ef47b713c46acc4257..946c6064a0979dbacb89b8f663eb140a969ba30a 100644
--- a/src/compiler/typer.cc
+++ b/src/compiler/typer.cc
@@ -247,6 +247,7 @@ class Typer::Visitor : public Reducer {
   static Type* NumberToInt32(Type*, Typer*);
   static Type* NumberToUint32(Type*, Typer*);
 
+  static Type* ObjectIsCallable(Type*, Typer*);
   static Type* ObjectIsNumber(Type*, Typer*);
   static Type* ObjectIsReceiver(Type*, Typer*);
   static Type* ObjectIsSmi(Type*, Typer*);
@@ -557,6 +558,11 @@ Type* Typer::Visitor::NumberToUint32(Type* type, Typer* t) {
 
 // Type checks.
 
+Type* Typer::Visitor::ObjectIsCallable(Type* type, Typer* t) {
+  if (type->Is(Type::Function())) return t->singleton_true_;
+  if (type->Is(Type::Primitive())) return t->singleton_false_;
+  return Type::Boolean();
+}
 
 Type* Typer::Visitor::ObjectIsNumber(Type* type, Typer* t) {
   if (type->Is(Type::Number())) return t->singleton_true_;
@@ -1988,6 +1994,9 @@ Type* Typer::Visitor::TypeStoreElement(Node* node) {
   return nullptr;
 }
 
+Type* Typer::Visitor::TypeObjectIsCallable(Node* node) {
+  return TypeUnaryOp(node, ObjectIsCallable);
+}
 
 Type* Typer::Visitor::TypeObjectIsNumber(Node* node) {
   return TypeUnaryOp(node, ObjectIsNumber);